CN216699066U - Erbium-doped fiber amplifier and communication system - Google Patents

Abstract

The utility model discloses an erbium-doped fiber amplifier and a communication system. The erbium-doped fiber amplifier comprises: a first channel fiber amplifier, a second channel fiber amplifier, and a two-in-one integrated device. The first channel fiber amplifier includes a first input port, a second channel fiber amplifier, and a second channel. An input optical power monitoring unit, a first bait fiber, a first integrated device and a first output port, and the second optical fiber amplifier includes a second input port, a second input optical power monitoring unit, a second bait fiber, and a second integrated device and the second output port. The first signal light is input from the first input port and sequentially passes through an input optical power monitoring unit, a two-in-one integrated device, a first bait fiber, and a first integrated device to the first output port; the second signal light is transmitted from the second input port Input and sequentially pass through the second input optical power monitoring unit, the two-in-one integrated device, the second erobium fiber, and the second integrated device to the second output port. The two amplifiers share a two-in-one integrated device, so that the two amplifiers can be integrated in the same package.

Description

Erbium-doped fiber amplifier and communication system

technical field

The utility model relates to the technical field of optical fiber communication, in particular to an erbium-doped optical fiber amplifier and a communication system.

Background technique

Erbium-doped fiber amplifier (EDFA) is an important device widely used in optical communication systems. EDFA can directly amplify the optical signal without complex processes such as photoelectric conversion, electro-optical conversion and signal regeneration. Because EDFA has the advantages of high gain, low noise, large bandwidth, and anti-electromagnetic interference, it is widely used in long-distance and large-capacity optical fiber communication systems.

At present, there are SFP (Small Form-factor Pluggable) and QSFP (Quad Small Form-factor Pluggable) packaged single-channel C-Band EDFA products on the market, using an uncooled 980nm pump laser, the output power can reach 17dBm.

However, most of the existing SFP and QSFP package products on the market are single-channel C-Band EDFA products, which can only achieve single-channel/unidirectional signal optical power amplification. And limited by the standard package, device size, etc., it is impossible to realize the design of integrating two amplifiers in the same package.

Utility model content

The utility model provides an erbium-doped optical fiber amplifier and a communication system, aiming at solving the problem that the existing SFP and QSFP packaging products are mostly single-channel C-Band EDFA products, which can only realize single-channel signal optical power amplification. And limited by the standard package, device size, etc., it is impossible to realize the design problem that two amplifiers are integrated in the same package.

In the first aspect, the present utility model provides an erbium-doped fiber amplifier, comprising: a first-path fiber amplifier, a second-path fiber amplifier, a two-in-one integrated device and a pumping unit, and the first-path fiber amplifier including a first input port, a first input optical power monitoring unit, a first bait fiber, a first integrated device and a first output port; the second optical fiber amplifier includes a second input port, a second input optical power monitoring unit, a second bait fiber, a second integrated device and a second output port; a two-in-one integrated device, used for connecting the first input optical power monitoring unit and the first bait fiber, and for connecting the second input optical power monitoring unit and the the second bait fiber; a pump unit, connected with the two-in-one integrated device, for providing pump light for the first bait fiber and the second bait fiber; wherein the first signal light is transmitted from the The first input port is input to the first output port and sequentially passes through the one input optical power monitoring unit, the two-in-one integrated device, the first bait fiber, and the first integrated device to the first output port; the second signal Light is input from the second input port and sequentially passes through the second input optical power monitoring unit, the two-in-one integrated device, the second bait fiber, and the second integrated device to the second output port .

Further, the two-in-one integrated device includes an isolator and a WDM, the first signal light is input to the WDM through the isolator, and the WDM outputs the first signal light and the pump light after multiplexing ; and the second signal light is input to the WDM through the isolator, and the WDM outputs the second signal light and the pump light after multiplexing.

Further, the pump unit includes a first pump laser and a second pump laser, both the first pump laser and the second pump laser are connected to the two-in-one integrated device, and the first pump laser and the second pump laser are both connected to the two-in-one integrated device. A pump laser is used for providing a first pump light for multiplexing with the first signal light, and the second pump laser is used for providing a second pump light for multiplexing with the second signal light.

Further, both the first pump laser and the second pump laser are 980 nm uncooled pump lasers.

Further, the two-in-one integrated device includes a first port for inputting the first signal light, a second port for inputting the second signal light, and a port for inputting the first pump light. a third port, a fourth port for inputting the second pump light, a fifth port for outputting a light beam obtained by combining the first signal light and the first pump light, and a fifth port for outputting the The sixth port of the light beam after the second signal light and the second pump light are combined.

Further, the first integrated device includes a first isolator, a first optical splitter, and a first photodiode used for output optical power monitoring, and the first signal light amplified by the first bait fiber passes through in sequence. The first isolator and the first optical splitter are output to the first output port, and the first optical splitter is used for splitting the first signal light to the first photodiode.

Further, the second integrated device includes a second isolator, a second optical splitter and a second photodiode used for output optical power monitoring, and the second signal light amplified by the second bait fiber passes through in sequence. The second isolator and the second optical splitter are output to the second output port, and the second optical splitter is used for splitting the second signal light to the second photodiode.

Further, it also includes a circuit control unit, the circuit control unit is connected to the first photodiode and the second photodiode, and the circuit control unit is also connected to the first input optical power monitoring unit and the first photodiode. The two input optical power monitoring units are connected, and the circuit control unit is configured to perform function control according to the input optical power and the output optical power, and the function control includes at least one of ACC, AGC, and APC.

Further, both the first erbium fiber and the second erbium fiber are erbium-doped fibers with an absorption coefficient of 80us or a signal of 165us.

In a second aspect, the present invention further provides a communication system, comprising an erbium-doped fiber amplifier, and the erbium-doped fiber amplifier is the erbium-doped fiber amplifier described in the first aspect.

Compared with the prior art, the beneficial effect of the present utility model is: by setting the first path fiber amplifier and the second path fiber amplifier, the first path fiber amplifier includes a first input port, a first input optical power monitoring unit, a first The bait fiber, the first integrated device and the first output port, and the second optical fiber amplifier includes a second input port, a second input optical power monitoring unit, a second bait fiber, a second integrated device and a second output port. The first optical fiber amplifier and the second optical fiber amplifier share a two-in-one integrated device, and the first signal light is input from the first input port and sequentially passes through an input optical power monitoring unit, a two-in-one integrated device, a first bait fiber, The first integrated device goes to the first output port; the second signal light is input from the second input port and sequentially passes through the second input optical power monitoring unit, the two-in-one integrated device, the second bait fiber, and the second integrated device to the second output port. Thereby, a two-in-one integrated device connects the first input optical power monitoring unit and the first bait fiber, and also connects the second input optical power monitoring unit and the second bait fiber, so that both amplifiers can pass through the two-in-one. The integrated device is used to transmit the optical signal, which greatly reduces the occupied space, and can realize the design of integrating two amplifiers in the same package to meet the requirements of miniaturization.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

1 shows a schematic diagram of an erbium-doped fiber amplifier according to an embodiment of the present invention;

FIG. 2 shows a schematic diagram of another embodiment of the erbium-doped fiber amplifier of the present invention;

3 shows a schematic diagram of a two-in-one integrated device of an erbium-doped fiber amplifier according to an embodiment of the present invention;

4 shows a schematic diagram of a first integrated device of an erbium-doped fiber amplifier according to an embodiment of the present invention;

FIG. 5 is a schematic diagram showing the function control of the erbium-doped fiber amplifier according to the embodiment of the present invention

11. The first input port; 12. The first input optical power monitoring unit; 13. The first bait fiber; 14. The first integrated device; 141, The first isolator; 142, The first optical splitter; diode; 15, the first output port; 21, the second input port; 22, the second input optical power monitoring unit; 23, the second bait fiber; 24, the second integrated device; 25, the second output port; 30, the second 40, a pump unit; 41, a first pump laser; 42, a second pump laser.

Detailed ways

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are part of the embodiments of the present utility model, not all of the embodiments. . Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

It is to be understood that, when used in this specification and the appended claims, the terms "comprising" and "comprising" indicate the presence of the described features, integers, steps, operations, elements and/or components, but do not exclude one or The presence or addition of a number of other features, integers, steps, operations, elements, components, and/or sets thereof.

It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural unless the context clearly dictates otherwise.

It should also be further understood that, as used in this specification and the appended claims, the term "and/or" refers to any and all possible combinations of one or more of the associated listed items, and including these combination.

Referring to FIG. 1, an embodiment of the present utility model provides an erbium-doped fiber amplifier, including: a first-path fiber amplifier, a second-path fiber amplifier, a two-in-one integrated device 30 and a pump unit 40, a first-path fiber amplifier, It includes a first input port 11, a first input optical power monitoring unit 12, a first erobium fiber 13, a first integrated device 14 and a first output port 15; the second fiber amplifier includes a second input port 21, a second input port The optical power monitoring unit 22, the second bait fiber 23, the second integrated device 24 and the second output port 25; the two-in-one integrated device 30 is used to connect the first input optical power monitoring unit 12 and the first lure fiber 13, and is used to connect the second input optical power monitoring unit 22 and the second bait fiber 23; the pump unit 40 is connected to the two-in-one integrated device 30, and is used for the first lure The optical fiber 13 and the second bait fiber 23 provide pump light; wherein, the first signal light is input from the first input port 11 and sequentially passes through the one input optical power monitoring unit and the two-in-one integrated device 30 , the first bait fiber 13, the first integrated device 14 to the first output port 15; the second signal light is input from the second input port 21 and sequentially passes through the second input optical power monitoring unit 22. The two-in-one integrated device 30 , the second bait fiber 23 , the second integrated device 24 to the second output port 25 .

Specifically, the erbium-doped fiber amplifier in this embodiment is a C-band erbium-doped fiber amplifier, and the erbium-doped fiber amplifier adopts a QSFP-DD package. Using QSFP-DD package can realize standardized product design, including electrical interface definition, software communication protocol, etc. In this embodiment, the first erbium fiber 13 and the second erbium fiber 23 are both erbium-doped fibers with an absorption coefficient of 80us or a signal of 165us, which can reduce the length of the fiber, reduce the saturation of the fiber and the difficulty of manufacturing the optical path.

By implementing this embodiment, a first channel of optical fiber amplifier and a second channel of optical fiber amplifier are provided, and the first channel of optical fiber amplifier includes a first input port 11 , a first input optical power monitoring unit 12 , a first bait fiber 13 , and a first integrated device 14 and the first output port 15 , the second fiber amplifier includes a second input port 21 , a second input optical power monitoring unit 22 , a second bait fiber 23 , a second integrated device 24 and a second output port 25 . The first fiber amplifier and the second fiber amplifier share a two-in-one integrated device 30, and the first signal light is input from the first input port 11 and sequentially passes through an input optical power monitoring unit, the two-in-one integrated device 30, and the first signal light. The bait fiber 13, the first integrated device 14 to the first output port 15; the second signal light is input from the second input port 21 and sequentially passes through the second input optical power monitoring unit 22, the two-in-one integrated device 30, and the second bait fiber 23. The second integrated device 24 to the second output port 25. Thus, a two-in-one integrated device 30 is connected to the first input optical power monitoring unit 12 and the first bait fiber 13, and simultaneously connects the second input optical power monitoring unit 22 and the second bait fiber 23, so that both amplifiers can be The optical signal is transmitted through the two-in-one integrated device 30 , which greatly reduces the occupied space, and can realize the design of integrating two amplifiers in the same package to meet the requirement of miniaturization.

In one embodiment, referring to FIG. 2 , the two-in-one integrated device 30 includes an isolator and a WDM, the first signal light is input to the WDM through the isolator, and the WDM converts the first signal into the WDM. The light and the pump light are combined and output; and the second signal light is input to the WDM through the isolator, and the WDM outputs the second signal light and the pump light after combining. Specifically, the isolator is used to realize reverse optical isolation, that is, the signal light can only travel from the input end to the output end, and cannot return from the output end to the input end, and isolate the optical signal from the output end to the input end. The first signal light enters the isolator through the first input optical power monitoring unit 12, and then enters the WDM through the isolator. Similarly, the second signal light enters the isolator through the second input optical power monitoring unit 22, and then passes through the isolator. Enter WDM. WDM (Wavelength Division Multiplexing) is a wavelength division multiplexer, which is used for coupling to combine two or more optical carrier signals of different wavelengths and couple them into the same fiber for transmission. The WDM in this embodiment is a WDM diaphragm. The WDM is used to combine the first signal light and the pump light and couple them into the first bait fiber 13 for gain amplification, and the WDM is also used to combine the second signal light and the pump light. and coupled into the second bait fiber 23 for gain amplification. Therefore, the isolator is integrated with the WDM through a two-in-one integrated device 30, the volume of the device is reduced, and more importantly, the first optical fiber amplifier and the second optical fiber amplifier share the integrated device, and the first signal light Both the optical signal and the second signal light can transmit the optical signal through the integrated device, which saves the device and greatly reduces the occupied space.

In an embodiment, referring to FIG. 2 , the pumping unit 40 includes a first pumping laser 41 and a second pumping laser 42, both of which are the same as the first pumping laser 41 and the second pumping laser 42. The two-in-one integrated device 30 is connected, the first pump laser 41 is used to provide the first pump light to combine with the first signal light, and the second pump laser 42 is used to provide the second pump Pu light is combined with the second signal light. Each fiber amplifier is equipped with a pump laser, which are the first pump laser 41 and the second pump laser 42 respectively. The first pump laser 41 emits the first pump light through the WDM and the WDM in the two-in-one integrated device 30 The first signal light is combined, and the second pump laser 42 emits the second pump light to combine with the second signal light through the WDM in the two-in-one integrated device 30 . Among them, the dual amplifiers use miniaturized 3PIN pin 980nm uncooled pump lasers, which are small in size and low in power consumption. The power consumption of the whole machine can be controlled to <3.0W. The first pump laser 41 and the second pump laser 42 all use 980nm uncooled pump lasers.

In other embodiments, the pump unit 40 includes a pump laser and a pump splitter. The pump light provided by the pump laser is split through the pump splitter to obtain the first pump light and the second pump light. The first pump light The pump light is combined with the first optical signal, and the second pump light is combined with the second optical signal. By using the pump laser and the pump optical splitter, only one pump laser can be used to provide two paths of pump light, which can be used to pump the first erotic fiber 13 and the second erotic fiber 23 respectively, saving energy. A pump laser is used to reduce the occupied space, reduce the volume, and meet the needs of miniaturization.

In a specific implementation, referring to FIG. 3 , the two-in-one integrated device 30 has six ports, namely four input ports and two output ports, the first to fourth ports are input ports, and the fifth and sixth ports are for the output port. Specifically, the two-in-one integrated device 30 includes a first port for inputting the first signal light, a second port for inputting the second signal light, and a second port for inputting the first pump light the third port, the fourth port for inputting the second pump light, the fifth port for outputting the combined beam of the first signal light and the first pump light, and the fifth port for outputting The sixth port of the light beam after the second signal light and the second pump light are combined. The first port and the second port respectively introduce the first signal light and the second signal light into the isolator, the third port and the fourth port respectively introduce the first pump light and the second pump light into the WDM, and the fifth port and the sixth port respectively lead out the combined beam. The size of the two-in-one device is required to be high <2.2mm (diameter)*23m (length), and the functional integration is high.

In one embodiment, the first input optical power monitoring unit 12 includes an optical splitter and a photodiode (not shown in the figure), and the first signal light is led out by the optical splitter and a beam of optical signals is incident to the photodiode, and the photodiode is transmitted by the photodiode. Perform photoelectric conversion to convert optical signals into electrical signals and provide them to the circuit control unit for power monitoring. The circuit control unit is a control circuit with a monitoring function, for example, a circuit composed of an MCU and its peripheral circuits. Similarly, the second input optical power monitoring unit 22 also includes an optical splitter and a photodiode. The optical splitter also splits the second optical signal into a photodiode. After the photodiode is converted, the circuit control unit performs power monitoring. Therefore, the present embodiment can monitor the input optical power through the first input optical power monitoring unit 12 and the second input optical power monitoring unit 22, and has hardware and software control functions at the same time, and can realize Disable control, EyeSafe safety power control, Monitoring alarm, module reset, module in-position monitoring and other functional requirements.

In one embodiment, referring to FIG. 4 , the first integrated device 14 includes a first isolator 141 , a first optical splitter 142 and a first photodiode 143 for output optical power monitoring, and the The amplified first signal light is sequentially output to the first output port 15 through the first isolator 141 and the first optical splitter 142, and the first optical splitter 142 is used to A signal light is split to the first photodiode 143 . Similarly, the second integrated device 24 includes a second isolator, a second optical splitter, and a second photodiode used for output optical power monitoring, and the second signal light amplified by the second bait fiber 23 It is output to the second output port 25 through the second isolator and the second optical splitter in sequence, and the second optical splitter is used for splitting the second signal light to the second photodiode. Specifically, the first isolator 141 is used to implement reverse optical isolation, and the second isolator is also used to implement reverse optical isolation. The first optical splitter 142 and the first photodiode 143 form a first output optical power monitoring unit, and the second optical splitter and the second photodiode form a second output optical power monitoring unit. The amplified first signal light enters the first beam splitter 142 through the first isolator 141 , and the first beam splitter 142 introduces a part of the beam into the first photodiode 143 for photoelectric conversion, and the other part of the beam is introduced into the first output port 15 output. Similarly, the amplified second signal light enters the second beam splitter through the second isolator, and the second beam splitter introduces a part of the beam into the second photodiode for photoelectric conversion, and the other part of the beam is introduced into the second output port 25 for output. . The device dimensions of the first integrated device 14 and the second integrated device 24 in this embodiment are required to be high <2.7 mm (diameter)*17 m (length), and the functional integration is high. On the one hand, the first integrated device 14 and the second integrated device 24 integrate the isolator and the optical power monitoring unit, which reduces the size of the device and reduces the occupied space; on the other hand, the monitoring of the output optical power is realized by using the optical power monitoring unit , both the input and output terminals realize the power monitoring function to ensure the reliability and safety of signal transmission.

In one embodiment, referring to FIG. 5 , the erbium-doped fiber amplifier further includes a circuit control unit, the circuit control unit is connected with the first photodiode and the second photodiode, and the circuit control unit is further connected with the first photodiode and the second photodiode. The first input optical power monitoring unit 12 is connected to the second input optical power monitoring unit 22, and the circuit control unit is used to perform function control according to the input optical power and the output optical power, and the function control includes ACC, AGC , at least one of APCs. The circuit control unit of this embodiment obtains electrical signals corresponding to the optical signals on the input side, such as voltage signals and current signals, through two input optical power control units, and obtains electrical signals corresponding to the optical signals on the output side through two photodiodes on the output side , such as voltage signals and current signals. Using the obtained electrical signals corresponding to the input side and output side optical signals, ACC control (Automatic Curent Control, automatic current control), AGC control (Automatic Gain Control, automatic gain control), APC control (Automatic Power Control, automatic power control) can be realized ). The module is highly intelligent and the control is simpler. Therefore, the erbium-doped optical fiber amplifier of this embodiment is a 2in1 C-Band EDFA product conforming to the QSFP-DD communication protocol standard, and integrates a control circuit to realize AGC/APC/ACC function control. To achieve miniaturization, low power consumption, high output power, hot swap, two-way amplification and other functions; and in order to achieve miniaturization requirements, can design and develop a variety of new miniaturized passive optical devices.

Embodiments of the present invention further provide a communication system, including an erbium-doped fiber amplifier, where the erbium-doped fiber amplifier is the erbium-doped fiber amplifier described in the above embodiments, which will not be repeated here.

By implementing this embodiment, product standardization is achieved, different communication systems can be used directly, and the demand for module application scenarios increases; low power consumption, <3.0W power consumption, the system does not need to consider additional heat dissipation design; flexible use, plug and play It takes up less space and reduces the difficulty of designing communication system boards. The erbium-doped fiber amplifier in this embodiment, as a dual-channel C-Band EDFA product in a standard QSFP-DD package, can support QSFP-DD slots and hot-swap functions, and can be applied in 5G mobile communications, data centers, etc. DWDM and ROADM systems of various network service providers.

In addition, the erbium-doped fiber amplifier of this embodiment can realize the integration of dual amplifiers in the QSFP-DD package. The performance of each amplifier can reach the performance level of single amplifier products in the market, and both channels can achieve a gain of 28dB/output power of 18dBm. . Among them, when the two-way communication system is applied, one slot can realize the requirement of two-way signal optical amplification, because it contains two independent amplifiers, one amplifier can realize the signal optical amplification in one direction, and the other amplifier can realize the signal in the opposite direction. Optical amplification, so that the amplification of two communication directions can be realized in one node, and the customer's use is more flexible.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection of the utility model.

Claims (10)

1. an erbium-doped fiber amplifier is characterized in that, comprising: The first optical fiber amplifier includes a first input port, a first input optical power monitoring unit, a first erobium fiber, a first integrated device and a first output port; The second optical fiber amplifier includes a second input port, a second input optical power monitoring unit, a second erobium fiber, a second integrated device and a second output port; A two-in-one integrated device is used to connect the first input optical power monitoring unit and the first erotic fiber, and is used to connect the second input optical power monitoring unit and the second erotic fiber; a pumping unit, connected with the two-in-one integrated device, and used for providing pump light for the first bait fiber and the second bait fiber; Wherein, the first signal light is input from the first input port and sequentially passes through the one input optical power monitoring unit, the two-in-one integrated device, the first bait fiber, and the first integrated device to the The first output port; the second signal light is input from the second input port and sequentially passes through the second input optical power monitoring unit, the two-in-one integrated device, the second bait fiber, and the second integrated device to the second output port. 2 . The erbium-doped fiber amplifier according to claim 1 , wherein the two-in-one integrated device comprises an isolator and a WDM, the first signal light is input to the WDM through the isolator, and the first signal light is input to the WDM. 3 . The WDM outputs the first signal light and the pump light after multiplexing; and the second signal light is input to the WDM through the isolator, and the WDM multiplexes the second signal light and the pump light. output. 3. The erbium-doped fiber amplifier according to claim 2, wherein the pumping unit comprises a first pumping laser and a second pumping laser, the first pumping laser and the second pumping The lasers are all connected to the two-in-one integrated device, the first pump laser is used to provide the first pump light to combine with the first signal light, and the second pump laser is used to provide the second pump Pu light is combined with the second signal light. 4 . The erbium-doped fiber amplifier according to claim 3 , wherein the first pump laser and the second pump laser are both 980 nm uncooled pump lasers. 5 . 5 . The erbium-doped fiber amplifier according to claim 4 , wherein the two-in-one integrated device comprises a first port for inputting the first signal light, and a first port for inputting the second signal light 5 . a second port, a third port for inputting the first pump light, a fourth port for inputting the second pump light, and outputting the first signal light and the first pump light a fifth port for the light beam after the optical combination, and a sixth port for outputting the light beam after the second signal light and the second pump light are combined. 6. The erbium-doped fiber amplifier according to any one of claims 1-5, wherein the first integrated device comprises a first isolator, a first optical splitter, and a first optoelectronic device for output optical power monitoring diode, the first signal light amplified by the first bait fiber is sequentially output to the first output port through the first isolator and the first optical splitter, and the first optical splitter is used to The first signal light is split to the first photodiode. 7. The erbium-doped fiber amplifier according to claim 6, wherein the second integrated device comprises a second isolator, a second optical splitter and a second photodiode for output optical power monitoring, The second signal light amplified by the second bait fiber is sequentially output to the second output port through the second isolator and the second optical splitter, and the second optical splitter is used to convert the second signal Light is split to the second photodiode. 8 . The erbium-doped fiber amplifier according to claim 7 , further comprising a circuit control unit, the circuit control unit is connected to the first photodiode and the second photodiode, and the circuit control unit It is also connected with the first input optical power monitoring unit and the second input optical power monitoring unit, and the circuit control unit is used to perform functional control according to the input optical power and the output optical power, and the functional control includes ACC, AGC , at least one of APCs. 9 . The erbium-doped fiber amplifier according to claim 8 , wherein the first erbium fiber and the second erbium fiber are erbium-doped fibers with an absorption coefficient of 80us or a signal of 165us. 10 . 10 . A communication system, characterized in that it comprises an erbium-doped fiber amplifier, and the erbium-doped fiber amplifier is the erbium-doped fiber amplifier according to any one of the preceding claims 1-9. 11 .

Images